The document discusses sleep scoring using the American Academy of Sleep Medicine (AASM) guidelines. It outlines the different sleep stages including light sleep, slow-wave sleep, and REM sleep. Electrodes are placed at specific locations to monitor brain waves, eye movements, muscle activity, and heart rate. There are two main sleep scoring methods, Rechtschaffen & Kales and AASM, and this document uses the AASM method. The characteristics of each sleep stage are then defined based on the patterns seen in brain waves, eye movements, and muscle activity.

1. Eva A.M. van Poppel
Sleep scoring using AASM

2. Hypnogram
Sleep Stages:
• Light sleep
• Slow-wave sleep (deep sleep)
• REM sleep

3. Frequencies
Epoch=30sec

4. Electrodes
F3 & F4
C3 & C4
O1 & O2
EOG (eyes)
EMG (chin muscle)
ECG (heart rate)
Typically, use the
even electrodes at
the right side of the
brain

5. Sleep scoring
There are 2 methods of sleep scoring
• Rechtschaffen & Kales (R&K, 1968)
• American Academy of Sleep Medicine
(AASM) (2007)
• We use AASM.

6. Sleep stage: 0
Wake (W).
Alpha in O1 & O2 (min 50% of epoch)
EEG: Low voltage, mixed frequency pattern.
Fast eye movements (usually lasting <500ms
and eye blinks (0.5 – 2Hz).

7. Sleep stage: 1
Alpha deminshes or disappears at sleep
onset.
Replaced by low voltage, mixed frequency
EEG pattern.
Slow rolling eye movements (sinus,
>500ms).
Vertex sharp waves, in θ

8. Sleep stage: 2
• Sleep spindles in C4: train of distinct waves
with frequency 11-16 Hz with duration >0.5
seconds
• K-complex in F4, high amplitude negative
sharp wave with total duration >0.5 seconds

9. Sleep stage: 3
Slow Wave Sleep
Also called delta sleep since there are high
amplitude waves in the delta range (0-4 Hz).
Stage 3 when >20% (6 seconds) of the
epoch contains Slow Oscillations with
frequency 0,5 – 2 Hz and amplitude >75 µV.
Use Frontal (F4) electrodes.

10. Sleep stage: 4
Slow Wave Sleep
Stage 4 when >50% of the epoch contains
Slow Oscillations with frequency 0,5 – 2 Hz
and amplitude >75 µV.
Not used anymore in AASM!

11. Sleep stage: 5
REM Sleep (R)
1. Low voltage, mixed frequency pattern,
no sleep spindles and K-complexes
2. Chin EMG no or lowest amplitude
3. Rapid Eye Movements
Sometimes sawtooth waves
90-120 min after sleep
onset
Sometimes no first cyclus
When people sleep in a new environment.

12. Sleep stage: 6 (MA)
Movement Arousal rule.
Score an arousal (6) together with the sleep
stage
when there is an abrupt shift of EEG frequency
including alpha, theta and or frequencies >16
Hz (no spindles) that last at least 3 seconds.
In REM an increase in EMG is required lasting
at least 1 second.

13. Major Body Movement
When there are movement artefacts for more than half
of a 30 seconds page epoch and the sleep stage cannot
be determined.
In AASM, apply the following rules:
• If alpha rhytm is present (even <15sec), score as
wake
• When there is no alpha, but there is an epoch before
or after the movement which is wake, score also as
wake
• Otherwise, score as the epoch that follows it.